[Haskell-cafe] Fwd: hackage compile failure with QuickCheck 2.5

[Ross Paterson]

With ghc 7.4.1, cabal-install 0.13.3 and Cabal 1.14.0,

% cabal install --avoid-reinstalls sbv-2.2

fails to find a plan without reinstalls, and recommends --solver=modular.

% cabal install --solver=modular --avoid-reinstalls sbv-2.2

reinstalls template-haskell-2.6.0.0, which breaks the GHC installation.

I've added the suggested --constraint='template-haskell==2.7.0.0'
option as a workaround, but it seems the --avoid-reinstalls option is
being ignored.